The field of the disclosure relates generally to printed circuit boards, and more particularly, to printed circuit boards having a profiled conductive layer and methods of manufacturing the same.
Power electronics systems generally include a printed circuit board and a plurality of electronic components mounted to the printed circuit board. Printed circuit boards generally include a plurality of conductive traces formed from a conductive layer to provide an electrical connection between the electronic components. Some printed circuit boards have multiple conductive layers, including inner conductive layers and outer conductive layers. In power electronics systems, it is desirable for printed circuit boards to have power and signal traces located in the same conductive layer, specifically the outer conductive layer. However, conductive traces used for power components need to be capable of carrying relatively large currents as compared to signal traces, and thus require relatively larger cross-sections. It is also desirable to minimize the spacing between traces in the outer conductive layer to improve the component density of the printed circuit board.
At least some known printed circuit boards include a relatively thick outer conductive layer to increase the current-carrying capacity of the power traces in the outer conductive layer. However, using thicker conductive layers limits the minimum obtainable distance between signal traces due to the processes used to pattern the outer conductive layer. In particular, chemical etching processes used to pattern the outer conductive layer causes undercutting of the conductive layer, resulting in traces having outwardly curved or slanted sides. As a result, the minimum obtainable distance between conductive traces generally increases as the thickness of the conductive layer increases.
Other attempted solutions have included adding conductive material to the power traces in a relatively thin outer conductive layer. Utilizing a thin outer conductive layer facilities decreasing the minimum spacing between conductive traces in the outer layer, and thus improves component density of the printed circuit board. However, adding conductive material to the outer conductive layer generally results in a non-planar outer conductive layer, requiring costly and complex procedures, such as the use of step stencils or complicated solder dispensers, during subsequent processing and assembly of components on the printed circuit board.